A study on emission and fuel consumption of motorcycles in idle mode and the impacts on air quality in Hanoi, Vietnam

ABSTRACT

This study aims to develop the models of emission and fuel consumption during idling of motorcycles (MCs) in Hanoi, including the unsteady and steady idling stages. Five MC models commonly used in Hanoi were selected to measure the instantaneous emission and fuel consumption rates under the controlled conditions at the laboratory conditions. The instantaneous emission and fuel consumption models during idling were developed for the test MCs in the unsteady idling stage. The R² of obtained models are higher than 0.9. The average emission and fuel consumption rates in the steady idling stages were determined. The average idling emissions of pollutants CO, CO₂, HC and NO_x were 60.9, 534.3, 10.3 and 1.8 g/h, respectively. The average fuel loss during idling is around 180 g/h. The emission released from the MC fleet in Hanoi during idling was estimated for the year 2018. The total idling emissions from the MC fleet of 3.9 million vehicles in the year 2018 of CO, CO₂, HC and NO_x were 6.5, 57.1, 1.1 and 0.2 kt, respectively. The total fuel loss during idling of the MC fleet in 2018 was ∼19.3 kt. The air pollutants eliminated in the idle mode as CO, CO₂, HC and NO_x contributed 2.23%, 3.19%, 1.14% and 1.03%, respectively, of the total emission from the MC fleet in Hanoi.

Abbreviations: CVT: continuously variable transmission; TWC: three-way catalytic; CVS: constant volume sampler; FR: fuel consumption rate; IR: infrared sensor; MC: motorcycle

Highlights

• The difference in the fuel used between steady and unsteady idle stages was identified.

• The instantaneous emission and fuel used models for unsteady idling were developed.

• The total fuel loss during idling of the motorcycle fleet in Hanoi was estimated.

• The total pollutant during idling of the motorcycle fleet in Hanoi was calculated.

KEYWORDS:

• Emissions
• idling
• fuel loss
• motorcycle
• Hanoi

Disclosure statement

No potential conflict of interest was reported by the author(s).